//Longest Common Prefix 
/*
#include <vector>
#include <time.h>
#include <math.h>
#include <algorithm>
#include <string>
#include <map>
#include <iostream>
using namespace std;

string longestCommonPrefix(vector<string>& strs) {
	string re="";
	if(strs.size()<1)
		return re;
	sort(strs.begin(),strs.end());
	for(int i=0;i<strs[0].length();i++){
		for(int k=1;k<strs.size();k++){
			if(strs[k][i]!=strs[0][i])
				return re;
		}
		re+=strs[0][i];
	}
	return re;
}
int main(){
	string p;
	int a[]={5,1,2,3,4};
	string s[]={"asdf","asd","as","as"};
	vector<int>v1(a,a+sizeof(a)/sizeof(int));
	vector<string>v2(s,s+4);

	cout<<longestCommonPrefix(v2);
	system("pause");
	return 0;
}
*/